Title: The profiles of radial liquid velocity and mixing parameters in multi-stage bubble columns

Authors: Haibo Jin; Yichen Lian; Ling Qin; Suohe Yang; Guangxiang He; Zhiwu Guo

Addresses: Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China ' Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China ' Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China ' Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China ' Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China ' Department of Chemical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China

Abstract: Liquid circulation flow is one of the important hydrodynamic characteristics of the multi-stage bubble column. In this paper, the radial liquid velocity, axial back-mixing coefficient, and liquid exchange velocity were studied in a multi-stage bubble column with 2,000 mm height and 282 mm diameter using a Pavlov tube and the tracer method. The effects of superficial gas velocity and plate structure on the mixing characteristics are presented. With an increase of the superficial gas velocity, the liquid velocity in the centre of the bubble column increases. With a decrease in the percentage of free area, the hole diameter, and tongue angle, the gas hold-ups below the perforated plate increases greatly. Moreover, the addition of a perforated plate enhances the eddy strength in the bubble column, which increased the coalescence and breakup of bubbles.

Keywords: multi-stage bubble columns; mixing characteristics; radial liquid velocity; axial back-mixing coefficient; liquid exchange velocity; liquid circulation flow; hydrodynamics; eddy strength; gas holdups.

DOI: 10.1504/IJEE.2015.069253

International Journal of Environmental Engineering, 2015 Vol.7 No.1, pp.35 - 49

Available online: 06 May 2015 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article